Naphtho[2,3-f]quinoxaline-7,12-dione compounds such as Formula I and Formula II are kinds of anthraquinone derivatives containing a heterocyclic group, where the synthesis and the effectiveness of the compounds to inhibit cancer cell activity through stabilizing G-quadruplex construction to suppress telomerase activity are both disclosed in Taiwan Patent Application No. 097112087.
The R4 is selected from hydrogen or methyl.
The known tricyclic anthraquinone derivatives, for example, the 2,3-dihydroimidazo[1,2-c]quinazoline compounds disclosed in Taiwan Patent No. 1378792; Taiwan Patent No. I402066; Taiwan Publication No. 201249792 and Taiwan Publication No. 200840582 can be used for the treatment of the excessive growth of cancer cells and the formation of the vessels accompanying the cells. In addition to the effects mentioned above, the compounds disclosed in Taiwan Patent No. I245036 not only inhibit tumor cell lines, but also have anti-allergic and anti-inflammatory properties as well. However, existing literature does not disclose whether anthraquinone derivatives can ease pain or can be applied to pharmaceutical use as an analgesic.
In order to overcome the drawbacks in the prior art, an indication of naphtho[2,3-f]quinoxaline-7,12-dione compound for alleviating pain is disclosed. The particular design in the present invention not only solves the problems described above, but is also easy to implement. Thus, the present invention has substantial utility for the industry.